<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>

  <style>
    .con {
      width: 300px;
      height: 100px;
      border-radius: 8px;
      box-sizing: border-box;
      border: 1px solid red;
      padding: 2px;
    }

    .textarea1 {
      width: 100%;
      height: 60px;
      box-sizing: border-box;
      padding: 0;
      margin: 0;
      outline: none;
      resize: none;
      border: none;
    }

    .textarea1::-webkit-scrollbar {
      width: 0;
    }

    .con:focus-within{
      /* border:1px solid blue; */
      background: linear-gradient(320deg, rgba(179, 71, 248, 1), rgba(246, 103, 48, 1), rgba(238, 34, 51, 1));
      
    }

    .down {
      margin-top: -4px;
      /* 不加这个-4px 会有间距 */
      width: 100%;
      height: 40px;
      /* border: 1px solid green; */
      box-sizing: border-box;
      background-color: #fff;
    }
  </style>
  <body>
    <div class="con">
      <textarea class="textarea1" name="ipt" id="iptt" title="111" placeholder="333"></textarea>
      <div class="down">1111111111111</div>
    </div>
  </body>
</html>
